This is a twin? Just use a length of hose and some motor oil : Airheads Beemer Club - $4 Carburetor Synchronizer
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This is a twin? Just use a length of hose and some motor oil : Airheads Beemer Club - $4 Carburetor Synchronizer
Pete, I have a Morgan carb tune if you want to use it.
Thanks guys, I think my home-made tool actually works quite well. I may add more RTV or something around the lines into the bottles just to be sure. I tried various iterations of the method Nhbubba linked, but found that it was too sensitive, even with 3 feet of water. The engine got a few mouthfuls. The bottle method was great, but glass bottles are definitely necessary. I tried with some hefty plastic bottles and the vacuum crushed them in about 3 seconds.
The chain is in bad shape, lots of tight spots and at least one missing o-ring that I noticed. I am obviously going to order a new one, but are o-ring chains "safe" to ride on a very limited basis with missing o-rings? I want to take it to work a few days while I wait for the chain to come in, I dont want the chain to decide to fly apart doing 80 on the highway.
Don't ever ride with a missing o-ring. Motorcycle will explode in a ball of flames causing instant death. We will all laugh at you.
Don't use water in the sync tool. Use something more combustion chamber friendly; motor oil (used will do), atf, etc.
What's wrong with water? I think its fine ignoring hydrolock concerns. But you can't compress motor oil or ATF either. Water's used as a cheap way to clean engines because it turns to steam. Usually sprayed in to the intake. And the turbo car crowd runs water injection to keep cylinder temps down. The viscosity of water might be why it didn't work well with the sync tool though?Quote:
Originally Posted by nhbubba
It's either that or in my mouth...Quote:
Originally Posted by TheIglu
I have a set of vacuum gauges that found their way to me over the years
Not as good as a manometer but easier and adequate
Turbo guys use water to keep the air charge cool, not the cylinders.Quote:
Originally Posted by aldend123
I think technically both are correct. The air charge is cooled by spraying water in to absorb ambient heat, as well as heat on metal surfaces, including the cylinder's combustion chamber. But let's get a source:Quote:
Originally Posted by number9
"Water/methanol injection systems deliver a finely atomized mist of a water/methanol mixture to an engine's cylinder charge, and as the mixture absorbs heat and vaporizes, temperatures inside the cylinder are reduced and the propensity for detonation is decreased." Water / Methanol Injection - Import Tuner Magazine
I did something really foolish, and decided to ride the beast to work today. I almost didn't make it. As soon as I came to a stop in traffic (on the highway!) it bogged down and cut out on me. With a bunch of throttle, it came back to life, but I quickly realized it wasn't going to work under 4k RPM. I dialed the idle up to about 4.5K and made it to work like that. It wasnt pretty. It seems ok above 6K, crappy from 4.5K-6K, and unrideable below 4.5K. I am confused because it seemed to be idling at 1.2K and revving from idle without any issues when I was testing it the other day. As soon as I put a load on it, it can no longer rev from idle and it bogs down. I twist the throttle and it kind of just chugs and sounds sickly, it will then die if I dont clutch in and rev it back up to 4K+. On deccel, it will backfire if I let it drop below ~4.5K.
Suggestions? I set the float height to spec when I had the carbs apart, but I did not attach clear lines to the bowl drains and check that it is actually working appropriately. Could this be a flooding issue?
Is it actually running on both cylinders at low RPMs?
I believe so, based on both header pipes getting hot. The header pipes are connected by another pipe right near the cylinders though, so that may not be a good way to tell.
Quote:
Originally Posted by Petorius
That is not a sign of flooding, IMO, I think it's running lean or not firing properly. Look for vacuum leak and check the spark plug wires. Some bikes of that vintage have 5000 ohm resistors in the plug wire caps and they can fail causing poor running at low RPM.
So my float heights were way off. Correcting this seems to have fixed the issues at low rpm. Here is where I'm at now:
If I give it light, steady throttle in first gear, it will pull smoothly from about 2.5K to 4K rpm. It will not climb above 4k without more throttle. If I then roll on a bit more, it hesitates, then lurches forward between about 4K and 5.5K. If I roll on smoothly to WOT, it gets a bit smoother above 6K, but still a bit lurchy.
If I give it medium throttle from the start, it pulls strong but is lurchy through the whole range above about 3k. WOT from start is similar. It hesitates, then jumps forward hard, then hesitates, then jumps, etc.
From digging around on the GS forum, it sounds like this is most likely a problem with the jet needle range. Currently the bike is bone stock, 100%. I cleaned/rebuilt the carbs. Spark plugs look perfect, PO claimed to have replaced and gapped them right before I picked it up, although I have not checked the gaps. PO also claimed to have checked and adjusted valve clearances within the last year he had it, although I have not checked them myself. I checked for vacuum leaks after the carb rebuild, did not find any. There is a slight oil leak from around the valve cover, very slight and did not affect idle when spraying around the cover gasket with WD40. Diaphragms also looked good, and I will check again next time I have the tank off.
My thoughts are to try raising the jet needle to see if adding fuel in the mid-range helps. Any other ideas? I have not looked hard at the spark plug wires yet, as suggested above.
Valve cover leak shouldn't impact the way it runs, it shouldn't impact vacuum. And if your valve adjustment was off, it'd either be really hard to start, or have poor top-end. Not sure it'd be so erratic. Sounds like you're on the right track with getting the fueling right in the carbs, but I lack the carb experience to say what to try.
I'm helpless regarding the carb tuning.
But why haven't you checked the valves yet?! Not saying thats your problem, but it is easy preventative maintenance.
I originally got the thing as a winter project. Didnt touch it until spring, of course, and now I just want to ride it. So I am prioritizing the things needed to make it rideable.Quote:
Originally Posted by nhbubba